To find out the equivalent marks and grade, you would need to:
1. Identify the specific board: Knowing the board (e.g., CBSE, ICSE, state board) is crucial.
2. Find the grading scale: Look for the official 2012 results' grading guidelines or conversion chart published by that board. This will show the GPA to percentage or mark conversion.
Without this information, it's impossible to give a definitive answer.